Re: List searching
- To: mathgroup at smc.vnet.net
- Subject: [mg57558] Re: List searching
- From: dh <dh at metrohm.ch>
- Date: Wed, 1 Jun 2005 06:01:46 -0400 (EDT)
- References: <d7h9gm$3go$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
HelloGuy,
see below
sincerely, Daniel
Guy Israeli wrote:
> Hello,
>
> I needed to test lists for certain elements inside of it, however, since I
> didn't find the proper function I had to write them myself.
>
> are there functions that can do the following:
>
> - tests (returns true or false) if within the list there is an element that
> appears more than once
we could use Mathematicas pattern matcher to do the job:
dat /. {{___, x_, ___, x_, ___} -> True, _List -> False}
this replaces a list with equal elements by True, if no match is found
the list is replaced by False. We can make this into a function:
# /. {{___, x_, ___, x_, ___} -> True, _List -> False}&
>
> - tests if there is an element in the list that is bigger/smaller than a
> certain number
a simple and fast way may be to test the Max/Min. E.g.
Max[dat]>5
if we want a function:
Max[#]>5&
>
> I would really appreciate your help,
>
> Guy
>
>